Electronic data storage has grown exponentially in volume with the parallel growth of the computer. With the growth in computer networks and, specifically, the internet, hundreds of exabytes (1018 or 10246 bytes) of data are currently stored on various computers, data servers, and other network devices worldwide, with that number surely to increase in coming years. Data search algorithms, software, and search engine systems have developed, in part, to help computer users navigate the vast swaths of data stored on private networks, the internet, or even their own computers. Some web search tools are implemented in web browsers, such as search engine prompts integrated into the web browser toolbar, shortcuts for favored web locations, and bookmarks.
The set of search results returned by a search engine is based on search algorithms employed by the search engine and the robustness of the dataset searched by the search engine. Search results returned by a search engine for a given search can sometimes be over- or under-inclusive. Some search engines allow a user to enter additional terms or modifiers to refine the search query, thereby generating a new set of search results based on the refined search.